Halo: Reach. Because you feel like your actions set in motion the entire trilogy. And the post-credit sequence was pretty thrilling. I felt like I could've taken on the entire Covenant. But that's just not the case. You will die. But you will go out fighting.

My #1 is definitely The Legend of Zelda: A Link to the Past. As a player, I actually felt like a hero during that ending sequence. It was just amazing in every way. A great sequence with awesome music.

My #2 is Mega Man 3 for the NES. It may not be a complicated ending, but the music & the revelation about Proto Man are just incredible. I also like how all the robots built by Dr. Light are properly listed along with their purposes. Although it's a small reason overall, this ending is yet another factor why Mega Man 3 is my #1 Mega Man game of all time and my #1 NES game of all.

Others I'd include:

Super Mario Bros. 2: I loved the dream ending and the music of the game. Even though it's a dream, the ending even allows for some stuff to happen & be explained if Nintendo were to take the route I'd like them to take.

Batman Returns (Sega CD) Full Game & Platform Game Endings: This game has 4 endings---the Full Game Ending, the Driving Game Ending, the Good Platform Game Ending, and the Bad Platform Game Ending. The Full Game Ending has Batman on top of a structure as a great score by Spencer Nilsen plays. The 2 Platform Game Endings has the player as Batman battling Catwoman as the credits are rolling down. If you as Batman win, you get the good ending, which is pretty messed up if you watch it. If Catwoman beats you, then you get the bad ending. The Driving Game Ending has the same score as the Full Game Ending, but is probably the weakest of the 4. Here they are for anyone who's interested:

Full Game Ending:[youtube]http://www.youtube.com/watch?v=s7oF-21IOdk[/youtube]

Driving Game Ending:[youtube]http://www.youtube.com/watch?v=J7XkpOuzyUc[/youtube]

Platform Game Good Ending:[youtube]http://www.youtube.com/watch?v=4yoIgxZngAU[/youtube]

The Super Castlevania IV ending is another one I really like. The Duck Tales games on the Game Boy & NES have some great endings too. Each one of those games has multiple endings (DT2 has 3), but I haven't yet decided which one I like more.